The transporting of articles via pneumatic tubes is old and well known. Basically, an object is placed within a container which is then transported by air under either positive or negative pressure from one destination to another. The transport is moved within a closed tube. The interior of the closed tube and the outer dimension of the carrier form a seal, so that the carrier can be propelled between the destinations by a vacuum.
One area of commerce which currently uses the pneumatic tube and the transporting of material via the pneumatic tube on a fairly regular basis is the hospital or biomedical research/manufacturing industry. One particular application of this technology is in the area of transporting blood samples, medicines, intravenous bags, viral samples or other biological or chemical matter between diverse locations within a hospital or laboratory. In that environment, for example, test tubes or vials of liquids are placed within a tube carrier, and are typically secured by foam or clamps within the carrier. The purpose of securing the samples (which are often contained within glass test tubes with rubber stoppers) is to help prevent breakage. When glass breaks or stoppers become dislodged (as can happen when hospital workers fail to properly secure the stopper in the first place), chemical or biological substances can leak into the interior of the carrier. In turn, said substances can leak out of the interior of the carrier, thereby contaminating the interior walls of the tube system. The vials or vessels of liquids, solids or gasses within the carrier can move or shift during transport, which may also lead to breakage. This problem is especially acute, as the carriers are often traveling at speeds in excess of 25 feet per second. Because of the rapid acceleration and deceleration of pneumatic tube carriers, the carrier contents can easily become dislodged, and can break within the carrier, if not for clamps, foam securing means, and the like. Nonetheless, accidents can happen, whereby despite the best efforts toward securing or protecting the interior vessels, they can break, or their stoppers can become dislodged. In fact, dislodged stoppers are a primary problem, due mainly to workers who may inadvertently fail to secure them properly in the first place.
If the leaking substance is of a large enough quantity, the substance (often a fluid) can leak out of the carrier. In that case, the entire tube transport system could become contaminated with the substance. For example, if fluids containing a virus or bacteria sample (for example, the HIV virus or the Ebola bacteria) were to leak out of a carrier, the interior of the vacuum transport tubes could become breeding grounds for the biological specimens--thus contaminating the exteriors of all carriers that pass through the system. Obviously, the recent public concerns over infectious diseases is a primary motivation behind the present invention. Also equally important is that fluids escaping from the carrier can "gum up" the interior of the vacuum tubes, making the smooth passage of the carrier difficult, resulting in enhanced downtime, increased maintenance expense, and increased power consumption (that is, friction would increase within the tube system).
If fluids escape from the vials and/or test tubes, but are contained within the carrier, the aforementioned problems can be mitigated. Of course, other problems can result. For example, a hospital worker may cut his or her hands on a broken vial when they proceed to open the carrier, and dangerous substances contained within the carrier may come in contact with the hospital worker. Also, in the case where toxic, aromatic substances such as toluene or benzene are being transported within vessels contained within the carriers, obviously, the worker would be placed in great danger if he or she opened the carrier under those circumstances. Basically, if a hospital worker opens a carrier expecting to remove sealed vessels and/or containers, and conversely, is presented with spilled contents (which may often be accompanied by broken glass, for example), then, the possibility of infecting the hospital worker or the overall tube system is great. For that reason, a watertight or airtight carrier could facilitate containing the hazardous substances within the carrier, so that vessels which may break or become unsealed in the transport process are contained within the carrier. Of course, problems can still result if workers open a carrier without knowledge of the hazardous conditions within. To safeguard against this event, the carrier could contain an indicator on its exterior that notifies the carrier handler of the interior circumstances--before the carrier is opened. In that case, if the interior contents are, for example, toxic gasses, the carrier may be opened in a controlled, safe environment.
There exists a need in the field to provide a carrier with suitable watertight and airtight properties, such that matter from within the carrier cannot escape to the outside, and matter that has become uncontrollable within the carrier can activate a warning indicator on the exterior of the carrier, so that hospital or other workers who use the carriers will not open carriers with uncontrolled contents (without ample warning that proper measures should be taken). That could be facilitated by a warning signal indicative of a spill or other abnormal condition within the carrier. Such a warning signal may even be a digital output, which can be decoded, to indicate what type of hazard lies within the carrier. Such a warning signal could also trigger a locking mechanism, making the opening of a carrier with spilled interior substances impossible without authorization and a form of key, electronic or otherwise. Also, based on the contents of the carrier, the locking mechanism may be activated so that only certain parties may be able to open the carrier, regardless of whether an uncontrolled substance is contained within. For example, if a dangerous controlled substance such as morphine is being transported, the carrier may be locked, and only certain authorized persons would be able to open the carrier.
Prior art known to the inventor includes U.S. Patent Nos. 4,948,303 to Good, 4,324,511 to Irish, 4,219,290 to Golston, 4,149,685 to Leavelle, and 3,825,210 to Weaver, which are incorporated herein by reference.
U.S. Pat. No. 4,948,303, granted to Good; discloses a pneumatic tube carrier with a reinforced hinge.
U.S. Pat. No. 4,324,511, granted to Irish, discloses a pneumatic tube carrier with an accelerator ring.
U.S. Pat. No. 4,219,290, granted to Golston, discloses a hinged pneumatic tube carrier with an improved side opening mechanism.
U.S. Pat. No. 4,149,685, granted to Leavelle, Apr. 17, 1979, discloses a pneumatic carrier having identical halves and includes means to adjust the latch mechanism.
U.S. Pat. No. Re. 30,882, granted, Mar. 16, 1982, to Leavelle is directed to an adjustable closure mechanism.
U.S. Pat. No. 3,825,210, granted to Weaver, Jul. 23, 1974, discloses a "clamshell" type pneumatic tube carrier of a bullet configuration wherein the seals which substantially fill the tube are not immediately adjacent the ends but are spaced therefrom.
U.S. Pat. No. 242,459, granted to Leaycraft Jun. 7, 1881, which discloses a pneumatic tube carrier having asymmetric hinged halves being continuously urged to a closed position by a spring means.
U.S. Pat. No. 359,456, granted to McLaughlin, Mar. 15, 1887, discloses a pneumatic tube carrier including a spindle or the like for wrapping a paper document for security during transportation from one location to another.
U.S. Pat. No. 452,471, granted to Barri, May 19, 1891, discloses a pneumatic tube apparatus wherein an opening in the surface of the container is created by twisting one coaxial section with respect to the other.
U.S. Pat. No. 769,233, granted to Pfluger, Sept. 6, 1904, discloses a cash box for use with a pneumatic tube wherein an opening in the carrier is exposed by relative twisting of the two coaxial elements.
U.S. Pat. No. 811,915, granted to Hager Feb. 6, 1906, discloses a pneumatic tube carrier including a specific stop member to prevent damage to the cylinders when the two coaxial halves are twisted relative to each other.
U.S. Pat. No. 1,169,553, granted to MacMillan, Jan. 25, 1916, discloses a means for securely latching a pneumatic tube carrier such that it does not accidentally open in transport.
U.S. Pat. No. 1,827,000, granted to Duffin Oct. 13, 1931, discloses a container for a roll of paper wherein the exterior container includes a hinge which connects two halves which are identical with the exception of an internal flap on one side for securing the container in a closed condition.
U.S. Pat. No. 2,251,238, granted to Busch, Jul. 29, 1941, discloses a pneumatic carrier wherein the coaxial halves are twisted with respect to each other to expose a window opening and includes a spring actuated locking device.
U.S. Pat. No. 3,401,902, granted to Gouyou-Beauchamps et al, Sept. 17, 1968, discloses a large dimension open top carriage for use in pneumatic conveying of large objects.
U.S. Pat. No. 3,593,948, granted to McClellan, Jul. 20, 1971, discloses a pneumatic carrier wherein identical halves are hinged together along one edge and includes spring means for urging the two halves to a closed cylindrical configuration for transport.
U.S. Pat. No. 3,761,039, granted to Hazell, Sept. 25, 1973, discloses a pneumatic carrier system including means for transferring documents from one individual carrier to another, enabling the use of sharp corners (transfer stations) in the transport tube itself.
U.S. Pat. No. 4,470,730, granted Sept. 11, 1984, to Wutherich discloses a pneumatic tube carrier having a separate pocket means to separate coinage from paper money during transport.
In general, pneumatic tube systems known in the art include a closed continuous passageway having a predetermined inner cross-sectional dimension where the passageway includes a plurality of curves or bends having a predetermined radius. A fluid, such as air, is controllably forced through the passageway in a loop to move a carrier through the passageway. In order for the carrier to move freely through the passageway, the dimensions, and in particular the length, of the carriers being used have been limited by the inner cross-sectional dimension and curvature radius of the passageway. Pneumatic delivery systems are used extensively for the rapid and efficient transportation of a wide variety of articles. These delivery systems are used in a number of business operations, including banks, hospitals, office buildings, industrial plants, and truck terminals as a few examples.
Pneumatic carriers for use in such delivery systems come in a wide range of sizes and shapes to accommodate the physical articles to be transported in the system. As an example, pneumatic carriers are provided for transporting cash, messages, stock transaction slips, letters, blueprints, electronic data processing cards, x-rays, pharmaceutical supplies, blood samples, narcotics, viral and bacteria cultures, and a variety of other small physical objects. A watertight carrier can be useful for transporting paper documents, by sealing out water or other material that can harm the paper.
In the past, various mechanisms have been utilized as closure devices for pneumatic tube carriers. For example, many such carriers include an end cap that is hinged with respect to a cylindrical hull on one side of the hull and which has a latch that fastens the end cap to the opposite side of the hull in a closed position. Such carriers employ a variety of fasteners, such as snap fasteners, elastic straps with holes that fit over hooks, or straps that may be secured to bendable posts.
Other types of pneumatic tube carriers are of the side opening variety. One conventional form of such a carrier employs two generally semi-cylindrical sections that are hinged along one longitudinal edge. The hinged sections may be swung toward or away from each other to effectuate opening and closing of the carrier hull. Locking is achieved by virtue of the end caps, which may be twisted to effectuate threaded engagement of the caps onto the carrier hull ends when the hinged hull sections have been closed. That is, the end caps are rotated in such a fashion as to be drawn towards each other onto the ends of the hull, thereby immobilizing the hull sections relative to each other. Rotation of the end caps in the opposite direction releases the hull sections and allows them to be opened.
One preferable configuration utilized by many carrier manufacturers is that of a side opening, wherein the two sides are hinged together, and the two sides are held together when the carrier is closed by use of a hook, or detent or indented type locking lip. Such carriers include latching mechanisms to prevent the door from coming ajar or opening during transit, which could cause the carrier to become lodged in the pneumatic tubes and would also allow the contents of the carrier to spill out into the tube system. In addition, the instructions for latching such side opening containers or carriers are simple to follow, so that the container can be easily placed within the tube system. Such hinging and locking mechanisms make waterproofing or sealing the carrier a particularly difficult task, as hinges and locks are embedded within the mold of the carrier, which is generally formed of plastic.
In another type of side opening pneumatic carrier, the access to the carrier is gained by simultaneously pulling and twisting the ends of the carrier to allow the side opening door to be opened. The instructions for such a two-step process are often difficult for many users to follow, and the physical effort and manual dexterity needed to simultaneously pull and twist both ends of the carrier against a spring resistance is often troublesome for many hospital workers.
A need has thus arisen for an improved type of pneumatic carrier which overcomes these and other disadvantages associated with the prior art devices. In particular, a need has arisen for a pneumatic carrier which can be easily opened, but which also maintains a watertight and airtight seal. Also, the carrier must be able to maintain its air and water tightness, despite the fact that it is subjected to a vacuum transport system, and despite the fact that it will be subjected to extreme environmental conditions, such as repeated use, frequent drops, dust and dirt particles, high speed travel and acceleration, and the like. The carrier could also have a supplemental sensor mechanism to indicate that interior abnormal conditions have developed.